The present invention relates to electric connectors, and more particularly to an interface card connector which greatly reduces the insertion force upon the insertion of an interface card, and firmly retains the inserted interface card in positive contact with respective terminals.
A regular electric connector for interface card is comprised of a casing having a longitudinal interface card insertion slot and two rows of terminals holes at two opposite sides of the interface card insertion slot, and a plurality of terminals respectively mounted in the terminal holes for connection to a circuit board. FIG. 6 shows an electric connector of this type. According to this electric connector, each terminal 60 comprises a smoothly arched springy portion 61 having a front end terminating in a downwardly extended contact portion 64 and a rear end terminating in a curved supporting portion 62 and then a mounting leg 63. When an interface card 65 is inserted into the interface card insertion slot, the downwardly extended contact portion 64 is retained in contact with a respective contact 651 at the interface card 65. This electric connector is still not satisfactory in function. The drawbacks of this structure of electric connector are outlined hereinafter.
1. When an interface card 65 is inserted into the interface card insertion slot, the inserted interface card 65 tends to be damaged by the rugged surfaces of the contact portions 64 of the terminals 60. If the gap between the two rows of terminals is relatively increased, the inserted interface card 65 may be moved relative to the terminals 60 when the electric connector is vibrated, causing the impedance to be increased. PA0 2. Because the contact portion 64 of each terminal 60 is not a plane, the contact area between the inserted interface card 65 and each terminal 60 is a point of contact. Therefore, the interface card 65 tends to be damaged from the contact portions 64 of the terminals 60 when it is inserted into the interface card insertion slot. When the electroplating layer of the interface card 65 is damaged, it tends to be covered with rust, and a broken circuit tends to be occurred. PA0 3. Because of point of contact between the inserted interface card 65 and each terminal 60, a high impedance is produced between the inserted interface card 65 and the terminals 60, and the machine may fail to work properly when a high temperature is produced during a high speed operation of the CPU of the circuit board to which the electric connector is connected. PA0 4. Because the terminals 60 are mounted in the terminal holes on the casing individually by labor, much labor cost is required. PA0 1. The fabrication procedure of the terminals 80 is complicated. PA0 2. When the terminals are inserted into the respective terminal holes on the casing 90, the endpieces 82 of the terminals 80 may be stopped against the bottom edge of the inside flange 92, causing the terminals 80 to be deformed or broken. PA0 3. The terminals 80 produce less clamping force to the inserted interface card, and the inserted interface card tends to be forced out of place when the electric connector is vibrated, causing the machine to fail. PA0 4. Because the mounting legs 84;86 of the terminals 80 are spaced from the material strip 87 at both sides before the terminals 80 are cut from the material strip 87, the terminals 80 tend to be deformed or damaged during delivery, processing, electroplating or packing.
FIG. 7 shows another structure of electric connector for interface card according to the prior art. According to this structure of electric connector, each terminal 80 comprises an endpiece 82 at one end retained to one side of an inside flange 92 inside the casing 90, a curved portion 81 extended from the endpiece 82, a contact portion 83 downwardly extended from one end of the curved portion 81 remote from the endpiece 82, a supporting portion 85 connected to one end of the contact portion 83 remote from the curved portion 81 and secured to a hole 91 on the casing 90, and a mounting leg 84 or 86 downwardly extended from one end of the supporting portion 85 for mounting in a hole on the circuit board. This structure of electric connector still has drawbacks. The drawbacks of this structure of electric connector are as follows: